I am new with lm35. So first I have uploaded just the basic code to get the output. It displays accurate data on 1602 LCD. But the problem is arising when I connect the arduino UNO with external 12V power supply.
As an example..
When the Arduino is powered from USB it displays 20.4*c-20.7*c. But when it is connected with 12V the temperature fluctuates from 11*c to 32*c.
Please help. Thank you.